Mendarda, Junagarh District, Gujarat
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Draft Report क� द्र�यभू�म �ल बो जल संसाधन, नद� �वकास और गंगा संर�ण मंत्रा भारत सरकार Central Ground Water Board Ministry of Water Resources, River Development and Ganga Rejuvenation Government of India Report on AQUIFER MAPS AND MANAGEMENT PLAN Mendarda, Junagarh District, Gujarat पि�चमी म鵍ा �ेत, अहमदाबाद West Central Region, Ahmedabad भारत सरकार जल संसाधन, नदी िवकास एवम् गंगा संरक् मं�ालय क��ीय भूिम जल बोडर GOVERNMENT OF INDIA MINISTRY OF WATER RESOURCES, RIVER DEVELOPMENT AND GANGA REJUVENATION REPORT ON AQUIFER MAPS & MANAGEMENT PLANS MENDARDA, JUNAGADH DISTRICT, GUJARAT STATE CENTRAL GROUND WATER BOARD WEST CENTRAL REGION AHMEDABAD REPORT ON AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADH DISTRICT, GUJARAT STATE 1. SALIENT FEATURES 1 Name of the Mendarda - 363.86 Km2 TALUKA& Area, 21°10’29” to 21°25’15” N Location(Fig-1) 70°20’48” to 70°34’27” E 2 No. of Town, villages 0, 66 3 District/State Junagadh/Gujarat 4 Population (2011 Male- 35440, Female- 33091, Total- 68,531 Census) 5 Normal Rainfall (mm) 858.78 mm- Monsoon Rainfall (IMD) (in mm) (Long Term) 50 969.60 mm -Average Monsoon Rainfall (in mm) (2003-12) 6 Agriculture (20015-16) Kharif Crops Rabi Crops Crop Area in Hact Crop Area in Hact Groundnut 22100 Wheat 500 Tal 0 Juvar 0 Castor 0 Castor 0 Gram 20 Bajri 0 Bajri 15 Tuver 45 Tuver 0 Mug 65 Mug 80 Udad 130 Mustered 0 Cotton 300 Isabgol 10 Sugarcane 0 Sugarcane 0 Vegetables 70 Vegetables 40 Fodder 750 Fodder 150 Gam Guvar 0 Jira 10 Soyabin 40 Onion 40 Coriander 3900 Garlic 30 Methi 10 Total 23500 Total 4805 7 Existing and future Sector Existing (MCM) Future water demands (MCM) (MCM) (Year 2025) Domestic and Industrial 1.99 2.68 Irrigation 52.43 31.38 8 Water level behaviour 12.98-17.00 m (Pre-monsoon) (2015)(Fig-2 & 3) AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 205 Fig-1: Location Map 1. Hydrogeology: Main aquifer in the areais basaltic aquifer (Fig. 2) where the ground water exists upto the depth of weathering and in the fracture zones wherever encountered in the depth. Two hydrogeological Cross sections are given in Fig. 3. Subsurface Hydrogeology As inferred from borehole data of the Mendarda Taluka, weathered and fractured Basalt forms the principal aquifer in the Taluka. Groundwater in this aquifer occurs under unconfined conditions and in the fractures encountered in the massive basaltic formation in the depth. The movement of groundwater is controlled by the extent of weathering, fracture and joints in the trap formation. Groundwater exploration has been done down to a max. depth of 437 mbgl and the average discharge ranges from 1 to 38 lps by compressor during drilling. AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 206 2. AQUIFER DISPOSITION Name of Aquifer Nature of Aquifer depth Nature of Compres Quality aquifer material aquifer and zone porosity sor encountered discharg (m) e Miliolitic Limestone Unconfined 0 to 7 Primary and - - Limestone secondary (Poreses, fractures and solution cavities) Deccan Trap Basalt Unconfined 0 to 37 Secondary ( 1 to 2 lps Fresh (Weathered weathered & and fractured) fracture) Deep Fracture Explore up to the Secondary Compress Fresh (Massive & depth of 437 m, (fractures, joints, or amygdolidal) zone shears and flow discharge encountered at contacts ) 10 to 38 50, 77, 138, 174, LPS 187, 214 & 429 m AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 207 Fig 2: Aquifer disposition of the area AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 208 Fig-3: Stratigraphic Section Depth to water level: Large part of the taluka is having depth to water level mostly between 10 to 20 m bgl in the central part of the taluka whereas the South-Western and North –Eastern fringe observed water level 20 to 40 m bgl (Fig. 4).One isolated patch of water level > 40 is shown in the North –Eastern boundary of the taluka. Decadal average water level mostly between the period of May 2006 and 2015 ranges from 10.98 to 18.55m bgl. (Fig5). The decadal average depth to water levels also depict almost similar picture, except deepest water levels of more than 20 mbgl are on the North-Eastern parts and large area is occupied by water levels between 10 and 20 mbgl (Fig.5). Long term groundwater fluctuation of water level for pre-monsoon and post- monsoon period are depicted in Fig. 6 & 7 for the period of 1987 to 2015. Ranges of the long-term fluctuation is given in Table below. Pre-monsoon(1987-2015) Post-monsoon(1987-2015) Rise Fall Rise Fall Min Max Min Max Min Max Min Max 2.54 3.60 -3.80 -10.20 0.40 15.88 Negligible AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 209 Fig 4: DTW Map (Pre monsoon) Fig 5: Decadal Average Depth to Water Level Fig.6 Absolute fluctuation Pre-monsoon Fig. 7 Absolute fluctuation Post-monsoon AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 210 Water Table map (Fig 8) shows water table are ranges 62.42 m to 135.02 m above msl and groundwater flow direction is from South-East to North-West. A groundwater mount is shown in the South-Eastern side of the Taluka. Fig 8: Water Table map with flow direction 3. Groundwater resource extraction, contamination. Dynamic GW Resources in MCM Total groundwater availability of the area is estimated in year 2013 is 86.49 MCM and total groundwater withdrawal for all purposes is 54.42MCM. The stage of groundwater development is 62.92% and the taluka is categorized “Safe” (Table 2). Table: 2 Groundwater resources 2013 S No. Item Fresh Saline Total 1 Area 363.86 - 363.86 2 Total GW Recharge (MCM) 91.04 - 91.04 3 Net GW Availability (MCM) 86.49 - 86.49 4 Gross Draft (MCM) 54.42 - 54.42 5 Net Availability for Future 31.38 - 31.38 Irrigation (MCM) 6 Stage of GW Development % 62.92 (safe) - 62.92 (safe) AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 211 In Storage GW Resources Fracture Fracture - age GW Resources (MCM) Resources GW age Saline/Brackish Area (sq km) Area (sq Saline/Brackish Fresh Area (sq km) (sq Area Fresh Name of Unit Assesment Formation of Rock Typr km) Area (sq Unit Total Depth of Bedrock(Soft upto Rock Areas/Depth which the aquifer is commonly Developed (HR Areas) (m) (m) in Level Water monsoon Pre Average Total saturated Thickness m Total Thickness saturated Thickness of the Granular Zone zone/Productive Zone below Premonsoon WL(M) Fraction (Sy) Yield Specific Average stor In FRESH (MCM) Resources GW storage In BRACKISH/SALINE MENDARDA Basalt 360.85 360.85 0 18.43 13.59 4.84 0.02 34.93 0.00 Weathered Basalt- 360.85 22.9 0.01 82.63 0.00 Massive- Fractured zone Milliolitic 3.53 3.52 0 21.79 14.96 6.83 0.1 2.40 0.00 Limestone MENDARDA 364.39 364.39 0 119.97 0.00 Total Chemical quality of groundwater Groundwater quality in general is good. Salinity is expressed in terms of total dissolved solids (TDS). Most of the area in the taluka (Fig. 9 ) falls TDS ranges 400 to 1440 mg/litre.Min. &Max. ranges of some of the constituents is given in the following Table. Taluka Total dissolved solids Cl F HCO3 Min Max Min Max Min Max Min Max Mendarda 400 1440 48 528 0 0.54 183 378 AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 212 Fig.9 Iso-TDS May 2015 Fig. 10 Iso-Chloride May 2015 Ground Water Issues • Sustainability of hard rock Aquifers • Non Availability of sufficient Surface Water for Irrigation. • Lack of awareness and involvement of stake holders in decision making. 4. Groundwater resource enhancement. Table-3Computation of volume (MCM) of water required for recharge Aquifer Volume of Specific yiled Volume of water Volume of rain unsaturated zone factor required for water planned avilable for recharge MCM for Artificial artificial recharge recharge (MCM) Basalt 345.66 0.02 6.91 0.59 AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 213 Table: 4 Computation of Recharge structures. Aquifer Area feasible Volume Volume of Volume No of No of for artificial of rain water of water Farm Check recharge Sq. water planned for planned Pond Dam Km planned conservation for (Unit (Unit for through recharge storage 0.05 Artificial Farm Pond through 0.05MCM) MCM) recharge Check (MCM) Dam Basalt 98.44 2.58 1.98 0.59 39 11 Financial Outlay of the Plan The total estimated cost of the Plan is 508.83 lakh, which includes Rs 88 lakh for ground water recharge activities, Rs 390 lakh (Farm ponds), 6.6 lakh for ground water monitoring (Piezometer construction) and Rs 24.23 lakh towards operation and maintenance charges. The tentative cost estimates of the various activities of the Plan are shown in Table 5. AQUIFER MAPS & MANAGEMENT PLANS MENDARDA TALUKA, JUNAGADHDISTRICT, GUJARAT STATE 214 Table: 5 Cost estimates of Recharge structures and monitoring well (Piezometers): Feasible Tentative Quantity Rainwater Tentative Total Expected Artificial Design (in nos. harvested unit cost tentative Annual GW Recharge & or area (mcm ) (in Rs cost (in recharge/ Water in sq. m) lakh) Rs lakh) conservation Conservation (mcm) structures/ activities Recharge Structures/ Activities Check Dam 11 0.55 8 88 0.50 Sub total 88 0.50 Water Conservation Activities ( 30 m x 30m x 1.5 Farm Pond (3 m) 39 1.95 10 390 1.365 fillings) 900 sq.m or 0.1 ha Impact assessment & Monitoring Up to 50 Piezometer 11 0.6 6.6 m bgl Impact assessment will be carried out by implemneting agency O & M - 5% of total cost of the scheme 24.23 TOTAL 508.83 Note: Type, number and cost of structure may vary according to site after ground verification The tentative location of villages for construction of Check Dams and their cost estimates are shown in Fig.